Checking the DNS settings and ensuring the Linux server is correctly resolving hostnames When Tableau Server on a Linux system is not accessible from client machines, the initial step should be to check the DNS settings. Ensuring that the Linux server can correctly resolve host-names is important for network accessibility. Incorrect DNS settings or issues with hostname resolution can prevent clients from accessing the server. Option A is incorrect because bandwidth allocation is typically not related to issues of server accessibility in a local network setting. Option C is incorrect as assigning static IP addresses to client machines does not address the accessibility of the server itself. Option D is incorrect because changing the network mode from public to private on the Linux server does not directly address accessibility or DNS resolution issues.